He has a steel, rounded shield; a five-sided, wooden shield; a red, white and blue surcoat; a protective vest; a wraparound helmet, pockmarked with dents; steel pads to hide his forearms, knees, legs and hands; and a blunt-edged sword designed to inflict pain but not cut. His collection cost about $4,000.

Ivey, a fitness trainer in Atlanta, will use all 60 pounds of the equipment Thursday at an outdoor arena in Aigues-Mortes, in the south of France. He will compete in his first Battle of the Nations, a modern-day, medieval-like combat involving national teams of fighters.

Ivey, 34, is among an estimated 500 participants from 22 countries entered in the four-day event.

Full-contact armored fighting events grew out of participation in historical re-enactments, which are largely theatrical and tame. More common re-enactment fighting involves wooden weapons in the United States. The Battle of the Nations, in its fourth year, is the first international full-contact competition of this scale that uses steel armor — a heightened risk factor that has attracted a certain breed of fighters. It has been won by Russia every year.

Many fighters are intrigued by a time when differences were settled by sword fights to the death.

“I’ve always been interested in history and war,” Ivey said. “To be able to get my mind around what it was like back then, I look at it from this perspective: If I lose the fight, that would be me dying out there.”

The Battle of the Nations consists of four fighting formats: 1 on 1; 5 on 5; 21 on 21; and all against all, in which some opposing squads join forces. Winners of each match are decided by which side has the last fighter, or fighters, standing. A combatant bows out when three body parts, which include the feet, are touching the ground. Matches involving fewer fighters are usually over within a couple minutes, while the all-versus-all match can last up to 10 minutes.

Elements of the competition have been borrowed from other sports. The referee, called the knight marshal, issues soccer-style yellow and red cards for rule infractions. Fighters are assigned positions similar to those in American football, like center, guard and flanker.

Jaye Brooks, 47, executive officer of the United States team, described the game strategy partly as keeping adversaries from getting behind a team’s players, similar to hockey and soccer.

Brooks, a senior project manager in Nashua, N.H., recruited a team of 50 fighters, including himself and his son Catlin, 25, for the event. Last year, Brooks said, participants needed to meet only two qualifications to make the squad: paying for a trip to Poland and “having the guts to do this.”

The United States finished fourth of 14 teams in its international debut last year, and 18 of the 29 members from that team returned. The average age of this year’s American players is 37. And while no woman has competed for the United States squad, Brooks said, a women’s division is being considered.

Ivey’s motivation to compete is similar to that of others who are willing to fight, with an understanding that injuries are possible. He described his mind-set as being like that of a soldier.

“It’s not something I want to do,” Cannata said. “It’s something I have to do.”

There are rules to the game, but not ones that are restrictive enough to eliminate serious injuries.

Unlike in traditional sports, equipment is inspected to ensure it conforms to the period in history that a particular competition is commemorating, based on historical findings and evidence.

Weapons must be blunted. Stabbing or thrusting, which Brooks defined as repeatedly delivering excess force to the same point of contact, is not allowed. Fighters can hit any region in the “kill zone,” which excludes the feet, back of knees, groin, back of neck and base of skull. Vertical strikes to the spine and horizontal strikes to the back of the neck are forbidden.

Injuries have included dislodged teeth and broken or severed fingers. In the United States, the athletes also undergo baseline testing to check for the possibility of concussions.

This year’s United States team will be accompanied by a support staff of 50 members, including a physician, a psychologist specializing in head trauma, cooks, armorers, knight marshals, squires and a masseuse.

But injury precautions and preventive measures can only do so much. Cannata, who has a background in fencing and martial arts, said, “The potential for life-altering injury is very serious.”

Brooks, who has torn knee muscles competing, will take any punishment that comes with recreating a period in history.

“This is the perfect sport for someone who wishes to participate in one of the roughest sports on earth, has a love of armor and weapons and Western martial arts, and a desire to be as close to being a knight of old as is possible in this modern age,” he said. “Most of us doing this sport dreamt as children of being a knight one day. Who knew we could make that dream a reality?”